Ulnar growth patterns in radial longitudinal deficiency.

PURPOSE: To determine the association between centralization surgical procedures and the longitudinal growth of the ulna in radial longitudinal deficiency (RLD).

METHODS: The charts of 90 patients with 124 affected limbs were reviewed. Thirty-four patients were affected bilaterally and 56 were affected unilaterally. Based on the Bayne and Klug classification there were 5 type I, 3 type II, 9 type III, and 107 type IV deformities. Seventy-two limbs had available radiographs, which were measured for ulnar length. We plotted 384 ulnar length measurements in 72 limbs and compared these with both normative ulnar length data and ulnar length data in RLD. The average ulnar length was compared for the group (n = 46) treated with surgical centralization versus the nonsurgically treated group (n = 22).

RESULTS: The nonsurgically treated group attained 64% of normal ulnar length whereas the nonnotched centralization group attained 58% of normal ulnar length. The notched centralization group attained 48% of normal ulnar length. Ulnar growth for the surgically treated group averaged 0.54 cm/y and the for the nonsurgically treated group averaged 0.71 cm/y, which showed no statistical significance.

CONCLUSIONS: Wrist centralization procedures effectively increase the overall length of the limb by centralizing the hand and carpus over the shortened ulna; this must be weighed against the high rate of recurrent radial deviation deformity and some loss of ulnar growth.